I'm in Utah at the Miller Motorsports park for my Boss Track Attack and they have a collection of extremely rare Ford cars and some rare assorted Ford parts. I came across this "Cross Boss" intake manifold and carb and I've never seen this before. You guys ever seen this ? Do you know if this thing is for a Clevor or a regular small block ?

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it is fore a boss 302, they are very rare. i once tried to buy a trans am preped full race 69 boss 302, the motor was scattered but it had the cross boss intake on it. the car was always a race car and was fully role caged. it was a competition orange car . this was several years ago ,i offered the guy $3000. for it . he told me he didnt want to sell it . ****ed me off when i heard he later sold the car for $2800
if i rember right the carbs are made by autolite . and i believe it was part of fords experimental line

it is fore a boss 302, they are very rare. i once tried to buy a trans am preped full race 69 boss 302, the motor was scattered but it had the cross boss intake on it. the car was always a race car and was fully role caged. it was a competition orange car . this was several years ago ,i offered the guy $3000. for it . he told me he didnt want to sell it . ****ed me off when i heard he later sold the car for $2800
if i rember right the carbs are made by autolite . and i believe it was part of fords experimental line

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You can see the Autolite stamp on the carb in the pic =)

So it is for a Clevor/Boss type motor. You are correct, if you look at the part number you will see it has the experimental part number designation.

SN Certified Technician

The carbs were used in trans am. Ford engineers taking advantage of the "single four barrel" rule as dictated by the SCCA back in the days of Boss 302 Trans Am racing decided to go the Weber style inline route as opposed to the standard, square 4 hole route to improve fuel distribution to #'s 1,4,5, and 8. Never used as a production carburetor for a street car, I don't think they even had an idle circuit.

And they are as rare as they come. When Ford decided to get out of racing in 1970,..they were no longer produced.

And I am drooling.

This was a publicity picture Ford offered the sanctioning body to help convince them that they were being made in enough quantity to get past the rule for homologation.

Admin Dude

I just saw that one of these intakes went for almost $5k on ebay. Here is the description that went with it:

Ford 302/351C CROSS-BOSS intake plus Autolite INLINE 4V carb - NOS

We have come across these rare pieces of Ford Racing history - new, unused, and sealed in the original parts boxes. This auction consists of a Ford "Cross-Boss" intake manifold (base plus top) PLUS a NOS matching Autolite inline 4-barrel carburetor, complete with original jetting and small parts kit. This intake fits Boss 302 engines, and was also used on Boss 351C engines using an adapter plate (not supplied).

Autolite Inline 4-V Carburetor:

The Autolite Inline carburetors came in two varieties - 850 cfm (P/N D0ZX-9510A, using 1 11/16" throttle bores) and 1425 cfm (2.25" throttle bores). This auction includes the larger version. Similarly, there were "early" and "late" versions of these carbs - this carb is a "Late" version (label indicates 1973), and it features a tunable idle circuit with two removable jets per venturi. The original jetting kit features a variety of idle, air bleed, and main-circuit jets, as originally supplied by Ford. Much of the criticism of running these on the street involved the "early" versions, which had no dedicated idle circuit. This carburetor is new and unused, and was found sealed in a plastic bag direct from Ford. Ford Part Number DOZX-9510B, it is dated 5/29/73 and features serial number 20390. The tuning manual for these carbs is available as a reprint and also may be found online at https://www.shoair.com/pdf/autoinlinecarburetor.pdf

This carburetor was shipped to Swanson/San Jose Ford of Los Gatos CA, via Air Freight (San Francisco), which of itself is pretty unusual. We also have the matching 875 cfm carb, available (with a matching top) on a different auction (290608309292). Both carbs were shipped via the same airbill from Ford Parts Central Office, Livonia MI. Team records indicate that engine and car testing was taking place at the same time at Laguna Seca Raceway, located a few miles away near Salinas California. The smaller carb and top combination apparently was used in that testing session.

Manifold top:

Part number DOZX-9C483-A, NOS, found sealed in original box.

Manifold base:

Very lightly used, apparently in a testing session. Box not available.

Tuning Aid (?):As part of this shipment, Ford Parts also included a base-plate for use under the carburetors. It features two very small ports on either side on the inside of each bore, counter-bored and threaded 1/8" NPT on the outside, intended for vacuum take-off, instrumentation, or ??. We are including this piece with the auction. It also is lightly used.

http://www.mustangsandmore.com/ubb/DanJones351CIntakes.html"There were two models of the Autolite in-line: P/N D0ZX-9510A flowing 850 cfm and D0ZX-9510B flowing a whopping 1425cfm. The smaller one was intended for the Boss 302 in Trans Am, hence the development of the Cross-Boss intake. The larger one was intended for the Boss 429. Intake manifolds of the 'bathtub type were also available from Holman & Moody for the 429 and Bud Moore for the Boss 302 and the 351C.

The Autolite inline 4 barrel carbs were developed as a way of dealing with the single 4 barrel rule imposed by the SCCA in Trans Am racing. The thought was since any 4 barrel carb was allowed, why not make a unit with the barrels all in a single row for better distribution. Inline carbs came in 2 versions. Part number DOZX 9510-A, aimed at Trans Am and NASCAR racing, used 1 11/16" throttle bores and was rated at 850 CFM. Part number DOZX 9510-B, aimed at drag and unlimited class racing, used 2 1/4" throttle bores and was rated at 1400 CFM.

Ford developed a companion 2 piece Cross Boss intake for use with inline carbs on Boss 302 engines and, with spacer plates, on 351C's. The basic

Cross Boss arrangement consisted of a lower plenum, part number DOZX 9425-A, with a bolt-on top cover, part number DOZX 9C483-A. The removable top made porting easier. The carbs themselves use a lot of off-the-shelf Autolite 2 barrel carb hardware. There were also calibration kits (part number D1ZX-9S549-AA) and gasket kits (part number D1ZX-9502-AA). These were strictly race carbs and were never equipped on any production vehicle. Early versions didn't even have idle circuits, requiring a delicate throttle adjustment just to get them to run @ 1500 rpm. Later versions were equipped with idle circuits that apparently worked quite well. In a 1973 test conducted by Ak Miller, a 351 Cleveland equipped with dual inline fours was tested against an open plenum tunnel ram equipped with a pair of conventional Holley 710 4 barrels. Low speed operation with the tunnel ram was termed "very poor" and the engine didn't start to work until 5000 rpm. The same engine equipped with an independent runner intake and a pair of the 1400 CFM Autolite inline fours faired much better. Peak horsepower matched the tunnel ram but, with the inline carbs and independent runner intake, the engine idled well at 600 rpm and pulled evenly across the rev range. Low speed operation was termed "fantastic". Ford had great plans for the inline carbs but like many of Ford's better ideas, the inline four died a premature death when Ford pulled out of racing in the '70's."

SN Certified Technician

I just saw that one of these intakes went for almost $5k on ebay. Here is the description that went with it:

Quoted only info I thought was relevant to the thread.

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sweeeeet. and look how clean and simple.
caution this image may be hazardouse to those with pace makers. sorry it may be a little grainy, its from my hot rod collection. this is a 289. you have to look this article up.

SN Certified Technician

What are those thing that look like fuel rails in the picture Noobz347 posted?

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Those are fuel rails, and that aint the carb in this thread. (Notice the lack of accelerator pumps on the driver side of the carb) That is a inline 4 hole throttle body on a Rousch offered engine that sells for ONLY 18k.

SN Certified Technician

always wanted to build a boss using the cleveland heads. i had a trans am block at one time and sold it .they have a high nickle content and the metal is a different color sort of like a dirty nickle, than a cast block and they dont rust as easy . just finding the right intake would be the trick. to bad this one is not available still. i know several old drag racers in the area,and i know atleast one of them has this intake but he will not turn loose of any thing. same guy has several un used SOHC 427 motors from his drag days and wont turn loose of any. he was sponsored by ford in the early 60s his drag car was a thunder bolt.

SN Certified TechnicianFounding Member

yes in fact i have seen one, well three actually, and all in the SAME place. there was a ford parts store in the LA area years ago that had three of them for sale, complete with the autolite inline carbs. two single carb intake tops and one twin carb intake top. i wish i had money at the time as all three set ups would have gone home with me, including the five inline carbs that they also had sitting around loose.

SN Certified Technician

yes in fact i have seen one, well three actually, and all in the SAME place. there was a ford parts store in the LA area years ago that had three of them for sale, complete with the autolite inline carbs. two single carb intake tops and one twin carb intake top. i wish i had money at the time as all three set ups would have gone home with me, including the five inline carbs that they also had sitting around loose.

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was that shop called ford power parts? i think that was the name .the guy used to stop by when ever he was in the area. i havnt seen him in quite a while. he had all kinds of ford goodys.

Those are fuel rails, and that aint the carb in this thread. (Notice the lack of accelerator pumps on the driver side of the carb) That is a inline 4 hole throttle body on a Rousch offered engine that sells for ONLY 18k.

Founding Member

Just a little second-hnd FYI on the Autolite four barrel. My former boss used to help out with a circle track car owned by a local Ford dealer and it ran an Autolite inline carb. He said it was by far the best carb he's ever tuned, no question about it. It had replaceable venturis and he also claimed a lot of the parts on the carb interchanged with the old single-barrel carbs found on Ford 6-cyliders! The more he talked about these carbs, the more they seemed to be like Weber carbs. I always wondered about making my own intake to fit two Webers inline on my small block.